Which of the following statements is true for a simple cubic unit cell?
There are eight atoms located at the corners of the cube
There are six atoms located at the corners of the cube and one atom at the centre of the cube
There is only one atom located at the centre of the cube
There are four atoms located at the corners of the cube and two atoms at the centre of the cube
In a simple cubic unit cell, there is only one atom located at the centre of the cube. The atom is shared equally between the adjacent unit cells, resulting in a total of one atom per unit cell. Therefore, option (c) is the correct answer.
In a simple cubic unit cell, the edge length is equal to the diameter of the atom, and the coordination number of each atom is 6 (i.e., each atom is surrounded by six neighbouring atoms). This type of structure is found in metals such as polonium and chromium, as well as in ionic compounds such as sodium chloride.